Air injector



Sept. 22, 1953 v. R. DIBBLE ET AL AIR INJECTOR Filed Jan. l0, 1951 7: j' ETAM IN V E N TOBS VAUGHAN RDIBBLE VAUGHAN R,DIBBLE,JR BMm ATTY.

from cylinder 2 said fluid flows to cylinder 2 causing pressure on piston 6 forcing the piston assembly downward, this being possible due to the fact that any pressure under piston 1 is released thru valve 35 which at this stage of operation of the device is open as illustrated in the drawing.

As the piston assembly moves downward under tank fluid pressure on piston 6 piston 5 enters cylinder 2 and the fluid pressure is removed from direct contact with piston 6 and placed on piston 5 causing further downward movement oi the assembly. During this downward movement and due to the differential of cylinders 2 and 3 a partial vacuum is set up between pistons '5 and 6 causing air displaced by the piston 5 and advanced thru air aperture 36 in cylinder 3 to bleed past the cupped leather of piston 6 and into space between pistons 5 and E and obviously as the piston assembly moves downward the cubic contents of that portion of cylinder 3 exposed to piston 5 is increased over that in cylinder 2 thereby increasing the vacuum between pistons 5 and 5 and the vacuum continues to increase until the cupped leather of piston 6 starts to pass aperture 3S at which time there is a rush of air thru the aperture and into the space between pistons 5 and E.

Substantially at this point of the downward stroke of the piston assembly the bottom end of shaft 8 and bushing 3) inserted therein contacts member 45 fixedly engaged on rod 25 by a pin il or other suitable means, and, as said assembly continues its downward stroke, said rod 25 thru said contact is moved downward tripping, thru means of pin 53, the conventional snap spring trigger assembly 2 and causing the closing of valve 35.

Up to the closing of valve 35 fluid passing thru orice 2li, tubular shaft S and therefrom into space below piston 1 is discharged thru said valve, now, with the valve closed, uid under tank pressure is built up below piston 'l and due to the increase in area of piston 'i over either piston 5 or 5 the piston assembly is caused to rise to position shown in the drawing causing the air pressure which has been built up between pistons 5 and 6 to a point greater than tank pressure, to be forced past piston 5 and into head 9 and therefrom thru boss Ill to the tank.

As the piston assembly approaches the end of its upward stroke bushing 3i) makes contact with nut it on the upper end of rod 25 causing 7- a pull cn the rod which is communicated thru pin iii, in the lower end of rod 25, to snap the spring assembly 2 causing the opening of valve 35 in preparation for another cycle of operation.

Since the previously described structure is primarily for water pressure systems wherein the pump is remote from the tank there is provided an alternate structure to be used with small tanks located adjacent the pump, of the centrifugal type or the like, the lower portion of which is illustrated in Figure 2, upper portion being substantially that shown in Figure 1, and wherein tubular shaft with end closures and outlets is replaced with a solid shaft 5B, rod 25 and spring snap assembly 2l are eliminated and a fitting 5i is substituted for valve 35.

In connecting this alternate structure into the water system the previously dened connection as in our preferred structure is made with the tank and tting 5l is connected thru suitable pipe ttings to the intake or suction side of the pump, said connection being made between the normal check valve in the line from pump to sources of water supply and the pump. Obviously with such connection of device with a water system the actuating of the device is subject to the operation of the pump because when pump is not in operation there is tank pressure on the under face of piston 'l as well as on pistons G or 5, Figure 1. However with the structure shown in Figure 2, when pump is actuated the pump suction drains the fluid pressure from below piston 'i allowing for the downward stroke of the piston assembly in a manner previously described in connection with structure shown in Figure 1, said downward stroke continuing until either the lower end of shaft 5i] covers the port thru fitting 5i or the pump is automatically shut off in which case there is a return of tank pressure below piston through the pump causing an upward stroke of the piston assembly.

The above description and drawings disclose several embodiments of the invention, as specic language has been employed in describing the several figures. It will, nevertheless, be understood that no limitations of the scope of the invention are thereby contemplated, and that various alterations and modifications may be made such as would occur to one skilled in the art to which the invention relates. For example, pistons 5 and 5 could be connected on a common rod while piston 'i could be mounted on a separate rod, thereby providing independent mountings for piston 7, although the latters piston rod would be arranged to engage piston ES so that the three pistons would move in unison.

What is claimed:

1. In an air injector device for a water system including a pump and a pressure tank, said air injector device including at least two cylinders, one of said cylinders having a smaller internal diameter than the other of said cylinders, means connecting said cylinders, at least two pistons of corresponding diameter to said cylinders, each piston being reciprocably mounted in each of said cylinders, piston rod means connecting said 1 pistons to each other, a head having an enlarged space forming a chamber of larger cross section than said smaller cylinder located 0n the opposite side of said cylinder of smaller diameter, than the other of said cylinders, said piston rod means being of a length whereby said smaller piston becomes disengaged from said smaller cylinder and enters said chamber when said smaller piston reaches one end of its movement.

2. In an air injector device for a water system including a pump and a pressure tank, said air injector device including at least two cylinders, one of said cylinders having a smaller internal diameter than the other of said cylinders,

means connecting said cylinders, at least two pistons of corresponding diameter to said cylinders, each piston being reciprocably mounted in each of said cylinders, piston rod means connecting said pistons to each other, a head having an enlarged space forming a chamber of larger cross section than said smaller cylinder located on the opposite side of said cylinder of smaller diameter, than the other of said cylinders, said piston rod means being of a length whereby said smaller piston becomes disengaged from said smaller cylinder and enters said chamber when said smaller piston reaches one end of its movement, said smaller piston having a cup leather facing toward said chamber.

3. In an air injector device for a water system including a pump and a pressure tank, said air injector device including at least two cylinders, one of said cylinders having a smaller internal diameter than the other of said cylinders, means connecting said cylinders, at least two pistons of corresponding diameter to said cylinders, each piston being reciprocably mounted in each of said cylinders, piston rod means connecting said pistons to each other, a head having an enlarged space forming a chamber of larger cross section than said smaller cylinder located on the opposite side of said cylinder of than the other of said cylinders, said piston rod means being of a length whereby said smaller piston becomes disengaged from said smaller cylinder and enters said chamber when said smaller piston reaches one end of its movement, the larger of said pistons hav-ing sealing means permitting bleeding movement of air around said sealing means and into said smaller cylinder.

4. In an air injector for use in a water system including a pump and a pressure tank, vertically aligned superposed differential cylinders, decreasing in size from a lowermost to an uppermost cylinder, a piston in each cylinder, means connectng the pistons together, said pistons being adapted to be motivated in one direction by flow of iiuid from the tank, a head on the uppermost cylinder adapted to communicate with the tank, said head forming a chamber of larger cross section than the inner diameter of said uppermost cylinder, said connecting means being of such a length whereby the piston in said uppermost cylinder becomes disengaged therefrom and enters the head chamber when it reaches the end of its movement upon being motivated in the other direction, and means connected to one of said cylinders for admitting air therein, and means connecting to the pistons for reciprocating the pistons in the other direction.

5. In an air injector for use in a water system including a pump and a pressure tank, said injector comprising at least two cylinders substantially vertically superimposed, said cylinders being of progressively increasing internal diameter, means connecting said cylinders, a piston in each cylinder, means connecting said pistons together whereby the pistons are movable as a unit, a head on the uppermost cylinder having a cross sectional area of greater size than the internal diameter of the uppermost cylinder, the area within the cylinders other than said uppermost cylinder being normally vented to the atmosphere, and means for causing upward and downward vertical movement of the pistons within said cylinders whereby air is injected into the tank, said connecting means being of a length whereby the piston in said uppermost cylinder becomes disengaged therefrom and enters said head during the end of the upward movement.

6. In an air injector device for a water system including a pump and a pressure tank, said device including three cylinders substantially vertically superimposed one upon the other, the uppermost cylinder having an internal diameter smaller than the intermediate cylinder and the intermediate cylinder having a smaller internal diameter than the lowermost cylinder, means connecting said cylinders, three pistons of corresponding diameter to said cylinders, means connecting the pistons together, each piston being reciprocably mounted in each of said cylinders, a head having a cross sectional area larger than the cross section of said uppermost cylinder, said connecting means being of a length smaller diameter,

whereby said pistons prior to the downward stroke thereof are positioned such that the second and third pistons are at the top of their respective cylinders and the rst piston is above and disengaged from its cylinder and in said head area, a vent to the atmosphere between said second and third pistons in said second cylinder, and means upon vertical movement of said pistons as a unit for `causing air to be injected into the tank.

7. The combination defined in Aclaim 6, wherein each of said pistons includes cupped leather portions, the cupped portions of the upper and intermediate pistons being directed upwardly and the cupped portions of the lower cylinder being directed downwardly.

8. An air injector for use in a water system including a pump and a pressure tank, said injector comprising vertically aligned superposed differential cylinders, decreasing in size from a lowermost to an uppermost cylinder, a piston in each cylinder, means connecting the pistons together, said pistons being adapted to be motivated in one direction by flow of iluid from the tank, means connected toone of said cylinders for admitting air therein, and means connected to the pistons for reciprocating the pistons in the other direction, a head on the uppermost cylinder adapted to communicate with the tank, said head forming a chamber of larger cross section than the inner diameter of said uppermost cylinder, said connecting means being of a length whereby the piston in said uppermost cylinder becomes disengaged therefrom and enenters said chamber when it reaches the end of its movement in the other direction.

9. In an air injector device for a water system including a pump and a pressure tank, the combination of vertically aligned outer and intermediate superposed differential cylinders, decreasing in sizes from a lowermost to an uppermost cylinder, housings creating the cylinders, a head on the uppermost cylinder for connecting it with a tank, and connected pistons in the cylinders motivated by now of fluid from the tank and arranged with the piston in the uppermost cylinder controlling communication between it and the head for injection of air into the tank against resistance of fluid under tank pressure with a low resistance pressure on downward stroke of the pistons and a high air injecting pressure on the upward stroke thereof, said head forming a chamber of larger cross section than the inner diameter of said uppermost cylinder, the connection between the piston in the uppermost cylinder and the piston in the intermediate cylinder being of such length whereby the piston in said uppermost cylinder becomes disengaged from said uppermost cylinder when it reaches one end of its movement and enters said chamber.

VAUGHAN R.. DIBBLE. VAUGI-IAN R. DIBBLE, JR.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 776,724 Caverno Dec. 6, 1904 1,139,991 Melmore May 18, 1915 1,163,724 Weld Dec. 14, 1915 1,184,447 Hammond May 23, 1916 1,941,766 Thom Jan. 2, 1934 2,447,173 Gordon Aug. 17, 1948 2,506,528 Webb May 2, 1950 

